• Title/Summary/Keyword: Green Chemistry

Search Result 942, Processing Time 0.059 seconds

Electroluminescence Characteristics of a New Green-Emitting Phenylphenothiazine Derivative with Phenylbenzimidazole Substituent

  • Ahn, Yeonseon;Jang, Da Eun;Cha, Yong-Bum;Kim, Mansu;Ahn, Kwang-Hyun;Kim, Young Chul
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.1
    • /
    • pp.107-111
    • /
    • 2013
  • A new green-emitting material with donor-acceptor architecture, 3,7-bis(1'-phenylbenzimidazole-2'-yl)-10-phenylphenothiazine (BBPP) was synthesized and its thermal, optical, and electroluminescent characteristics were investigated. Organic light-emitting diodes (OLEDs) with four different multilayer structures were prepared using BBPP as an emitting layer. The optimized device with the structure of [ITO/2-TNATA (40 nm)/BBPP (30 nm)/TPBi (30 nm)/Alq3 (10 nm)/LiF (1 nm)/Al (100 nm)] exhibited efficient green emission. Enhanced charge carrier balance and electron mobility in the organic layers enabled the device to demonstrate a maximum luminance of 31,300 cd/$m^2$, a luminous efficiency of 6.83 cd/A, and an external quantum efficiency of 1.62% with the CIE 1931 chromaticity coordinates of (0.21, 0.53) at a current density of 100 mA/$cm^2$.

Application of radiotracer technique in remediation of Zn(II) from aqueous solutions by dry cowdung powder

  • Shaikh, Sabrina Afzal;Bagla, Hemlata Kapil
    • Nuclear Engineering and Technology
    • /
    • v.54 no.2
    • /
    • pp.456-461
    • /
    • 2022
  • Heavy metal pollution is caused due to anthropogenic activities and is considered as a serious environmental problem which endangers human health and environment. The present study deals with biosorption, an eco-friendly technique for the removal of heavy metal Zn(II) from aqueous medium. Various natural materials have been explored for the uptake of metal ions, where most of them are physically or chemically enhanced. Dry cowdung powder (DCP) has been utilized as a low-cost, environmentally friendly humiresin without any pre-treatment, thus demonstrating the concept of Green Chemistry. Batch biosorption studies using 65Zn(II) tracer were performed and the impact of different experimental parameters was studied. Results revealed that at pH 6, 94 ± 2% of Zn(II) was effectively biosorbed in 5 min, at 303 K. The process was spontaneous and exothermic, following pseudo-second-order reaction. The mechanism of heavy metal biosorption employing green adsorbent was therefore elucidated in order to determine the optimal method for removing Zn(II) ions. DCP has a lot of potential in the wastewater treatment industry, as seen by its ability to meet 3A's affordability, adaptability, and acceptability criteria. As a result, DCP emerges as one of the most promising challengers for green chemistry and the zero-waste idea.

Liquid Chromatography of Non-Chromophores by Indirectly Photometric Detection (간접 분광광도 측정에 의한 비발색단의 액체크로마토그래피)

  • Sam-Woo Kang;Hae-Beom Oh;Young-Ja Moon
    • Journal of the Korean Chemical Society
    • /
    • v.31 no.2
    • /
    • pp.184-189
    • /
    • 1987
  • Brilliant green was examined as a detection reagent in the separation of some aliphatic alcohols, ketones and esters by the reverse-phase liquid chromatography. These samples not possessing chromophore could be indirectly detected by photometric detector with the assistance of brilliant green in visible range (625nm). Some mixtures of samples were also able to separated and detected with good base line resolution and comparatively high sensitivity.

  • PDF

Potentiality of Green Fluorescent Protein (GFP) from Aequorea victoria - A Mini Review

  • Karagozlu, Mustafa Zafer;Kim, Se-Kwon
    • Journal of Marine Bioscience and Biotechnology
    • /
    • v.5 no.4
    • /
    • pp.26-32
    • /
    • 2011
  • Green fluorescent protein (GFP), a very important biological agent that involves shifting the color of bioluminescence from blue to green in luminous coelenterates and to increase the quantum yield of light emission. GFP discovered in medusa, Aequorea victoria is a key factor of various biotechnological and cell biological applications. Beside these applications, GFP of A. victoria is generally stable, which does not require co-factors for activity and can be functionally expressed in different bacterial species. This property of GFPs from A. victoria permits them to be a unique tool to monitor gene expression and protein localization in different organisms. The present review brings out the past milestones and future perspectives on GFPs, with an elaborative reviewing on its applications.

Polymerization and Characterization of Polyesters Using Furan Monomers from Biomass (Biomass 유래 퓨란계 단량체를 이용한 폴리에스터의 중합 및 특성 연구)

  • Seo, Kang-Jin;Kim, Myeong-Jun;Jeong, Ji-Hea;Lee, Young-Chul;Noh, Si-Tae;Chung, Yong-Seog
    • Polymer(Korea)
    • /
    • v.35 no.6
    • /
    • pp.526-530
    • /
    • 2011
  • Furan-2,5-dicarboxylic acid (FDCA) was synthesized by $KMnO_4$ oxidation of 2,5-dihydroxymethylfuran(DHMF) derived from biomass. Polyesters were synthesized by esterification and polycondensation of FDCA with various diols(ethane-1,2-diol, propane-1,3-diol, butane-1,4-diol, hexane-1,6-diol, decane-1,10-diol). The composition of polyesters was characterized by using $^1H$ NMR. Thermal properties of the polyesters were characterized by DSC and TGA. Intrinsic viscosities(IV) of the polyesters were measured to be 0.78~1.2 dL/g comparable with IV of commercial poly(ethylene terephthalate)(PET). As the chain lengths of diols increased, Young's modulus and strength decreased and elongation-to-break generally increased. Young's modulus and strength of the polyesters were measured to be 3551 MPa and 103 MPa, respectively, comparable with commercial PET.

Control of Late Blight of Tomato and Potato by Oilgochitosan (올리고키토산에 의한 토마토 역병과 감자 역병의 방제)

  • Cho, Yong-Ho;Choi, Gyung-Ja;Kim, Byung-Sup;Jang, Kyoung-Soo;Yoon, Mi-Young;Park, Myoung-Soo;Kim, Jin-Cheol
    • Research in Plant Disease
    • /
    • v.17 no.2
    • /
    • pp.129-135
    • /
    • 2011
  • Chitosan is a linear polysaccharide composed of randomly distributed ${\ss}$-(1-4)-linked D-glucosamine and Nacetyl-D-glucosamine. There have been many reports on the induced systemic resistance and in vivo antifungal activities of higher molecular weight chitosans with molecular weights over 3,000 amu (atomatic mass unit), but there are few papers on in vivo antifungal activities of low molecular weight chitosans (oligochitosans) with molecular weights less than 3,000 amu. In our study, an oligochitosan sample (320.3,000 amu) showed a potent 1-day protective activity with control values more than 94% at concentrations of 500 and 1,000 ${\mu}g$/ml especially against tomato late blight caused by Phytophthora infestans under growth chamber conditions. It also displayed a moderate 1-day protective activity with control values of 67.89% at concentrations of 500 and 1,000 ${\mu}g$/ml against wheat leaf rust and red pepper anthracnose. On the other hand, it showed a 16-hr curative activity against red pepper anthracnose, but not against tomato late blight and wheat leaf rust. In field experiments, oligochitosan effectively suppressed the development of late blight on potato and tomato plants with control values of 72% and 48%, respectively. The results strongly indicate that oligochitosan can be used as an eco-friendly organic material for the control of late blight on tomato and potato plants.

Blue-green Electroluminescence from Aluminum and ${\alpha}$-pyridoin Complex

  • Kim, Won-Sam;Lee, Burm-Jong;Tuong, Nguyen Manh;Son, Eun-Mi;Yang, Ki-Sung;Kwon, Young-Soo
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.605-608
    • /
    • 2004
  • A novel blue-green emitting aluminum complex was developed by employing 8-hydroxyquinoline as co-ligand for enhancement of electron transport and light emission abilities so that the electroluminescent (EL) devices do not need additional electron transport layer. The aluminum complex (PAlQ) of 8-hydroxyquinoline and ${\alpha}$-pyridoin was synthesized The structure of the PAlQ was elucidated by FT-IR, UV-Vis and XPS. The PAlQ complex showed thermal stability up to 350$^{\circ}C$ under nitrogen flow by TGA. The photoluminescence (PL) was measured from solid film of the PAlQ complex on quartz substrate. The EL device was fabricated by the vacuum deposition. The device having the structure of ITO/TPD/PAlQ/Al was studied, where N,N-bis(3-methylphenyl}-N,N'-diphenyl-benzidine (TPD) was used as a hole transporting layer. The EL device emitted a blue-green light.

  • PDF